xfs: pass bmapi flags through to bmap_del_extent

Pass BMAPI_ flags from bunmapi into bmap_del_extent and extend
BMAPI_REMAP (which means "don't touch the allocator or the quota
accounting") to apply to bunmapi as well.  This will be used to
implement the unmap operation, which will be used by swapext.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 1ec3087..ee9f54b 100644 (file)
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -4765,7 +4765,8 @@ xfs_bmap_del_extent(
        xfs_btree_cur_t         *cur,   /* if null, not a btree */
        xfs_bmbt_irec_t         *del,   /* data to remove from extents */
        int                     *logflagsp, /* inode logging flags */
-       int                     whichfork) /* data or attr fork */
+       int                     whichfork, /* data or attr fork */
+       int                     bflags) /* bmapi flags */
 {
        xfs_filblks_t           da_new; /* new delay-alloc indirect blocks */
        xfs_filblks_t           da_old; /* old delay-alloc indirect blocks */
@@ -5057,7 +5058,7 @@ xfs_bmap_del_extent(
        /*
         * If we need to, add to list of extents to delete.
         */
-       if (do_fx) {
+       if (do_fx && !(bflags & XFS_BMAPI_REMAP)) {
                if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK) {
                        error = xfs_refcount_decrease_extent(mp, dfops, del);
                        if (error)
@@ -5075,7 +5076,7 @@ xfs_bmap_del_extent(
        /*
         * Adjust quota data.
         */
-       if (qfield)
+       if (qfield && !(bflags & XFS_BMAPI_REMAP))
                xfs_trans_mod_dquot_byino(tp, ip, qfield, (long)-nblks);
 
        /*
@@ -5400,7 +5401,7 @@ xfs_bunmapi(
                        cur->bc_private.b.flags &= ~XFS_BTCUR_BPRV_WASDEL;
 
                error = xfs_bmap_del_extent(ip, tp, &lastx, dfops, cur, &del,
-                               &tmp_logflags, whichfork);
+                               &tmp_logflags, whichfork, flags);
                logflags |= tmp_logflags;
                if (error)
                        goto error0;

diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h
index 8e69b53..9c04067 100644 (file)
--- a/fs/xfs/libxfs/xfs_bmap.h
+++ b/fs/xfs/libxfs/xfs_bmap.h
@@ -101,6 +101,9 @@ struct xfs_extent_free_item
  * Map the inode offset to the block given in ap->firstblock.  Primarily
  * used for reflink.  The range must be in a hole, and this flag cannot be
  * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
+ *
+ * For bunmapi, this flag unmaps the range without adjusting quota, reducing
+ * refcount, or freeing the blocks.
  */
 #define XFS_BMAPI_REMAP                0x100